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Topic: Macerator and Plumbing Modification on a U225? (Read 2170 times) previous topic - next topic

Macerator and Plumbing Modification on a U225?

I am thinking about getting a macerator but am puzzled how to hook it up to the 4" Thetford exit fitting on the coach.
I have never been happy with this particular dump setup to begin with, so modifying the exit to the side, rather than thru the floor is something I would like to accomplish at the same time and the 4" Thetford seems to be an oddball in the RV plumbing world.
These are photos of what I have now.
Any thoughts?

Re: Macerator and Plumbing Modification on a U225?

Reply #1 –
I have one, can't remember the brand, but it came in a case. It attaches to the main dump pipe with a bayonet fitting so It can be removed easily when you want to use the conventional dump system.
Works great.
I use it at home if I want to dump my tanks. I run it to a sewer dump about 100' from the coach.
Make sure you have the largest diameter drain hose you can otherwise the back pressure puts a huge strain on the pump motor especially if your pumping a great distance.

Re: Macerator and Plumbing Modification on a U225?

Reply #2 –
So I understand--- you want to cut a HOLE in the basement door???

Re: Macerator and Plumbing Modification on a U225?

Reply #3 –
Quote from: wolfe10 –
So I understand--- you want to cut a HOLE in the basement door???
No, I'm thinking of opening the door. I'd like to add a 3rd valve and maybe some clear plastic pipe. The existing pipes are 4" and, unless I'm mistaken, most coaches now use 3" pipes with Valterra fittings.
Right now, there is hardly enough room under the RV to connect a dump hose, let alone whatever adapters I would need to hook up a macerator. I'm thinking if the exit port was horizontal instead of vertical it would be easier for an old man to deal with.
Obviously I want it keep this as simple as possible.
Maybe I should keep my existing plumbing as it is and put the macerator & adapter(s) on the end of my dump hose.

Re: Macerator and Plumbing Modification on a U225?

Reply #4 –
Quote from: Dakota Slim –
I am thinking about getting a macerator but am puzzled how to hook it up to the 4" Thetford exit fitting on the coach.
Leave the door closed - use the existing dump pipe plus:

1.  Short Thetford to Valterra adapter    Valterra T05-2285VP Sewer Hose Connector | eBay

2.  Clear 90 degree Valterra to Valterra:    Valterra Sewer Hose Connector T1023 | eBay

3.  Macerator should connect to clear 90.    Amazon.com: Flojet 18555-000A Portable RV Waste Pump with Garden Hose...
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Macerator and Plumbing Modification on a U225?

Reply #5 –
Quote from: Chuck & Jeannie –
Leave the door closed - use the existing dump pipe plus:

1.  Short Thetford to Valterra adapter    Valterra T05-2285VP Sewer Hose Connector | eBay

2.  Clear 90 degree Valterra to Valterra:    Valterra Sewer Hose Connector T1023 | eBay

3.  Macerator should connect to clear 90.    Amazon.com: Flojet 18555-000A Portable RV Waste Pump with Garden Hose...
Thank you! I wasn't aware that a clear 90 existed.
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Macerator and Plumbing Modification on a U225?

Reply #6 –
Quote from: Dakota Slim –
Maybe I should keep my existing plumbing as it is and put the macerator & adapter(s) on the end of my dump hose.
You want to keep the macerator pump as close to the coach as possible because you need to run a power cable from your battery to the pump.  Also, the water supply hose needs to be close to the waste tank so you can flush the tank with clean water to assist the dumping action.

Re: Macerator and Plumbing Modification on a U225?

Reply #8 –
I would strongly advise to avoid any kind of permanent installation that doesn't allow quick removal of the macerator.  They will clog with hair and you have to disassemble and clean out the blades.  The only way you can avoid this is by disallowing all long haired individuals from entering your coach but I don't think most of us would want to do that ;)  My "clean dump" system has had some pretty disgusting moments ;) 

Re: Macerator and Plumbing Modification on a U225?

Reply #9 –
As Chuck stated, The FloJet is the way to go, hooks right up with the bayonet fitting, and you drain right out of a standard garden hose.  It comes with alligator clips to clip onto your battery posts.  I just wired mine directly to the light fixture and it works great.

Re: Macerator and Plumbing Modification on a U225?

Reply #10 –
Quote from: hdff –
Chuck is this adapter a 4" to 3"??  I would like something that would adapt directly to modern day 3" to the stock 4" thedford.
AFAIK all the Thetford and Valterra RV connections are a standard size, whether you call it 3" or 4" I don't know.

I believe the adapter I linked will work to mate a white Thetford RV 2-pin to a Valterra RV 4-pin hose or device.

Re: Macerator and Plumbing Modification on a U225?

Reply #11 –
Quote from: Chuck & Jeannie –
AFAIK all the Thetford and Valterra RV connections are a standard size, whether you call it 3" or 4" I don't know.

I believe the adapter I linked will work to mate a white Thetford RV 2-pin to a Valterra RV 4-pin hose or device.
A few years ago, my 4" dump hose ruptured as I was dumping. I hastily bought a Valterra hose kit (No refunds at the campground) only to find that the Valterra bayonet didn't work and the Valterra 3" hose was too small for the 4" Thetford connector.

Re: Macerator and Plumbing Modification on a U225?

Reply #12 –
What I was trying to say above is that all the Thetford 2-pin RV connections are the same size, and all the Valterra 4-pin RV connections are the same size.  I'm not saying Thetford and Valterra are the same size...they are different sizes.

A commonly available Thetford to Valterra adapter will work with both systems.

Re: Macerator and Plumbing Modification on a U225?

Reply #14 –
I would cut the Thetford part off of the black abs pipe and get a valterra fitting and glue it on and then you will not need to have any adapter.

Re: Macerator and Plumbing Modification on a U225?

Reply #15 –
Quote from: red tractor –
I would cut the Thetford part off of the black abs pipe and get a valterra fitting and glue it on and then you will not need to have any adapter.
I agree, but the OP said he wanted to keep it "as simple as possible".

Even if he glues on a Valterra connector, he will still need a 90 degree adapter to get the macerator pointed horizontal to ground.

Re: Macerator and Plumbing Modification on a U225?

Reply #16 –
Be advised that the Valterra 90 degree connector is very flimsy especially when you attach the weight  and torque of the macerator to it. You need a way to help reduce the stress on the fitting or the bayonet will break, it will also leak because the gasket and mounting ears are cheap.

Re: Macerator and Plumbing Modification on a U225?

Reply #17 –
I had to totally rebuild the drainage plumbing on both the waste tanks in my 1981 Foretravel. The valves were obsolete. One had a slight leak and then a rock that had wedged between 2 of the rear tires flew out and cracked one of the drain pipes and that started leaking. I added a 3rd valve and really liked having no surprises when I opened the cap.
This U225 has Valterra valves and I wonder why Foretravel used a Thetford connector at the end. Regardless, a macerator makes sense for me now and if I'm going to do any cutting of the abs I'd like to add a 3rd valve and knowing that clear 90 degree connector is a weak link makes me want an alternative solution.
Thanks to all for your input! 
Has anyone used the Sureflo 3200? The ebay seller has sold over 800 of them....
Shurflo 3200 Macerator Pump NEW RV MARINE 3200-000 3200-001 | eBay

Re: Macerator and Plumbing Modification on a U225?

Reply #18 –
Quote from: Dakota Slim –
This U225 has Valterra valves and I wonder why Foretravel used a Thetford connector at the end. Regardless, a macerator makes sense for me now and if I'm going to do any cutting of the abs I'd like to add a 3rd valve and knowing that clear 90 degree connector is a weak link makes me want an alternative solution.
I can only assume that the Thetford dump hose system was more popular or more prevalent at the time the coaches were built.

Our coach also came with the Thetford connector.  The previous owners had accumulated several Thetford to Valterra adapters that came with the spare parts collection.  None of them worked well - they all leaked.  I followed the Forum standard recommendation and converted to a third dump valve plus Valterra connection.  BUT, I had a LOT more room to work with.  The threads linked below might give you some ideas on how to rig up a third valve that still leaves room to connect a macerator device.

Third Waste Gate Valve

Problems with third dump valve mod

Recent third dump valve installations (split from another topic)

Third dump valve on an '02-'04 generation coach?


Re: Macerator and Plumbing Modification on a U225?

Reply #19 –
Thanks for the links Chuck & Jeannie. They cover just about everything someone can run into, including disassembling the existing abs pipes. In my U225 think I need to go back to the "Y" where the black and grey pipes merge, redesign and then build, adding a 3rd valve with a horizontal outlet that I can connect a hose or macerator to.